The terrible experiences of his native Poland and of his generation were vividly expressed in the poetry and plays of Tadeusz Różewicz, who has died aged 93. The second world war haunted Różewicz until his death, but so did the moral obligation to write about it because, as he wrote in I Did Espy a Marvellous Monster: "At home a job / awaited me: / To create poetry after Auschwitz." His first two volumes of poetry, Anxiety (1947) and The Red Glove (1948), were revolutionary in creating a new idiom to express the horrors he had witnessed. What he wrote was so different from prewar Polish poetry that he was credited with creating a new prosodic system in Polish verse affecting not only the poets who came after him but established poets too. The writer Seamus Heaney called him one of the great European poets of the 20th century.

Różewicz's poems were ascetic, without metre, rhyme or metaphors, stripped bare of any rhetorical posturing and ornamentation or anything that could be considered aesthetically pleasing, to reflect the loss of absolute moral and cultural norms after the war. They attempted to answer the essential question of how to live in a post-Holocaust world. In what is probably his best-known poem, The Survivor, Różewicz wrote: "Virtue and crime weigh the same I've seen it: in a man who was both criminal and virtuous."

His later poems became a form of internal dialogue that worked in "non-poetical" elements including press clippings, references to his interest in visual art, and quotations from philosophers or writers such as Camus, Saint Augustine, Dostoevsky, Françoise Sagan and Federico Fellini. In this way, he mirrored the contradictions of the postwar world, as in his longer poem from 1963 entitled Falling, about the upward and sideways elements in the life of modern humanity. He concludes: "In the past one fell and was raised vertically, now one falls horizontally."

Equally revolutionary and experimental was his drama, especially his seminal The Card Index (1961), the first of 15 published plays. Sometimes considered indebted to the theatre of the absurd, Różewicz's play was, in fact, a dialogue with Beckett's nihilism. It revolutionised Polish theatre, not by imitating reality but, rather, by creating what he called "a self-contained reality on stage". The open structure of his plays defied the established theatrical conventions in using a nameless character, an anti-hero who mostly lies in bed and does nothing; episodes that do not advance any specific storyline; and a lack of psychological characterisation. All this prompted a discussion on the postwar generation paralysed by war, and its later participation in Stalinism.

The Card Index was followed by The Witnesses or Our Little Stabilisation (1962) and The Old Woman Broods (1968), plays in which even words were no any longer seen as a necessary part of a drama, while still affirming Różewicz's talent as a modern prophet who discusses many essential issues, such as the destruction of the natural environment, visualised as trash passing through the window of a coffee shop.

Born in the small town of Radomsko into the family of a court clerk, Różewicz had two brothers, Janusz and Stanislaw. The boys' education was interrupted by the war, and Janusz, who was also a poet, helped Tadeusz to enlist in the Home Army, the underground resistance movement in occupied Poland. Janusz was executed by the Germans. For two years, Tadeusz fought in a guerrilla unit in occupied Poland, writing his first poems.

With his work translated into more than 40 languages and awarded many prizes, Różewicz was seen as a great humanist and a moral authority, despite his unquestionable pessimism. In 1999, he published a collection of poems, family documents, photos and essays entitled Mother Departs, for which he received the Nike prize, the most eminent Polish literary award. He dedicated it to his mother, Stafania, who came from a Jewish family that had earlier converted to Christianity.

Różewicz saw himself as an atheist. In Word After Word (1994) he wrote:

It's time time is running out

what am I to take with meto the other shorenothing

so is thisall mum

yes son

this is all …

... so this is the whole life

yes the whole life

Różewicz is survived by his wife, Wiesława, whom he married in 1949, and their sons Kamil and Jan.